Wednesday, May 15, 2013

Honey bees at center of controversy

Neonicotinoids are toxic to bees and other
pollinators, especially when sprayed directly.
Applications of neonicotinoids directly to
flowering plants during daylight hours should
be avoided, per label directions.

What could present a more peaceful, bucolic image than the scene of beekeepers tending their bee hives? Beekeepers are traditionally seen as the gentlest of agriculturalists, not killing anything for food but merely reaping the labor of an industrious insect in exchange for nurture and protection. Yet there is little peaceful about the verbal and political battle swirling about beekeepers and honey bees at the moment.

In case you haven't heard, the domestic bee industry in the U.S. and in other countries around the world was hit hard in 2006 with puzzling bee and colony losses, since referred to as Colony Collapse Disorder (CCD). In a typical year beekeepers expect to lose 10-15% of their colonies to disease and various stresses. Since CCD arrived, colony losses have averaged 30% each winter, a significant increase. Despite dire headlines warning of the doom of agriculture, according to one 2012 report, the costs of CCD to consumers so far seem to be minimal and honey bee colony losses have been compensated for effectively by beekeepers themselves.

Nevertheless, something seems wrong with the world if bees are dying. And when a possible cause of bee declines is a pesticide, the debate is sure to get lively.

The smoking gun for environmentalists opposed to neonicotinoids came in the form of studies reported last year that show that one of the sub-lethal effects of low exposure neonicotinoids include loss of the bees' sophisticated ability to find their way back home. This loss of homing ability would account for one of the more distinctive symptoms of CCD, namely colonies that slowly decline with no signs of dead bees around the hive. Other forms of colony decline typically include dead bees around the colony entrance.

While there is no doubt that neonicotinoids are toxic to bees at high enough doses, scientists are still divided on the question of whether bees that forage on neonicotinoid-treated crops are exposed to high enough levels of toxicant to suffer from flight disorientation, and whether there is even a correlation between CCD and neonicotinoid use. Indeed, in some parts of the world where neonicotinoids are extensively used, such as Australia, CCD is not reported to be a problem.

If you work in the pest control industry, by now you should be asking yourself the question, "If my company uses neonicotinoids on a customer's property, are we harming our community's bee populations?" No one wants to be a bee killer.

If scientists who study bees are divided on the cause of bee risks from pesticides, it's likely that the answer to this question will be complex. But here are some points that might be useful as you consider how to handle this issue within your own company, and in discussing these insecticides with your customers.

Both the USDA and EPA recently issued a report summarizing positions that CCD is a result of multiple factors, not just pesticides.

All labels are approved on the basis that when used according to label directions the pesticide must not pose unreasonable adverse to humans or the environment, including honey bees. The EPA has recently reviewed registrations for some of these insecticides and stands by its risk/benefit assessment that these products can be used safely if the label is followed.

While research is suggestive of a potential risk to bees from agricultural uses of neonicotinoids, the case is far from proven. And so far, to my knowledge, no credible sources have suggested that urban residential uses of neonicotinoids pose any unusual risk to bee colonies in urban areas.

The greatest potential risk to bees from neonicotinoids appears to be in agricultural settings, where bee colonies are exposed to large acreages of treated plants. The diversity of plants and the relatively low use of pesticides in urban settings argues for lower potential risks in residential and commercial landscapes.

Although neonicotinoids, like most nervous system toxins, are relatively toxic to birds, there is no pattern of bird deaths associated with appropriate use of neonicotinoids, as claimed by some.

Neonicotinoid insecticides are moderately low in toxicity to people and mammals due to some unique nerve junction differences between us and insects. Just because an insecticide is toxic to bees doesn't mean that it has broad ecological toxicity.

Use of neonicotinoid sprays should be avoided on flowering plants during daylight hours. Bees are at high risk when sprayed directly, or if they contact wet spray deposits. In residential and commercial landscapes, neonicotinoids can often be applied effectively through root injection, greatly minimizing risks to pollinators like bees.

If your company includes neonicotinoids in its IPM toolbox, take a look at how you are using these products. If you are using products like Premise®, Merit® or Optigard® outdoors, are you restricting sprays to non-plant surfaces, plant root zones and soil? Are your technicians aware of the risks and possible negative public perceptions of neonicotinoids, and are they well-informed enough to communicate how your company minimizes environmental risks when they are used?

Neonicotinoids are effective and valuable insecticides for a variety of structural and landscape pests. For some landscape pests there are no highly effective alternatives. It's up to all of us to ensure that these products are used safely and in accordance with label instructions. Good product stewardship is essential if we want to keep the use of neonicotinoids and maintain a "green" reputation in our communities.

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NOTE: Neonicotinoid insecticides are a relatively new class of systemic insecticides that make up approximately 20% of the global pesticide market. The first neonicotinoid to be introduced to the pest control market in the U.S. was Premise®, the first non-repellent termiticide. The active ingredient in Premise®, imidacloprid, remains at the center of the CCD controversy because of its widespread use in agriculture and in the ornamental landscape market. Other common neonicotinoids mentioned in the bee controversies include chlothianidin (Arena®), thiamethoxam (Optigard®), and to a lesser extent, acetamiprid (Transport®). Neonicotinoids are important insecticides for the control of termites, fleas, and bed bugs, and outdoors against sap-feeding insects such as scales, aphids and whiteflies.

3 comments:

I would like to congratulate you on a well written article. I feel this way as your blog is based response neutrally, as a researcher should, not biased, as media tends to produce to garner support for their position.

50 years from now, I’d love to see humankind in balance with nature: Few chemicals, polyculture, and butterflies and bees a plenty. Today, however, that’s a pipe dream. Reality has farmers overworked and gaining their expertise from IPM’s and other industry experts. They don’t have the opportunity or bandwidth to understand alternative methods.

Chemicals are a requirement, monoculture is the best method to get crops grown for low costs, and politics & companies are all in bed together leaving the consumer, farmer, and bees at their mercy. I realize this is an overblown left-leaning statement. I believe there is a balance that should be struck. What that is, still has to be determined.

To find this balance we need to find collaborators with common visions to slowly shift current practices towards more “earth centric” ones. Not knowing you, my sense is that you see things correctly. At some point, I’d love to have a conversation with you to determine if you’d like to participate with a group of collaborators with that strategic vision.

Thank you for this article, Mike. It’s shocking how many ‘exterminators’ include inappropriate insecticides in their IPM and fail to read the fine print on how to use them properly. Hopefully more of them will learn soon and keep the bees safe!

Thanks for a balanced opinion. I found this article while searching for another... a great article that pushed through the paranoia to point out that colony collapse disorder has been well-documented even prior to human interference and heavy chemical use, and also that losing the honeybees would not result in our extinction. I had read it a month or two ago, and wanted to go back and add a bookmark it. Couldn't find it. I only found dozens of article predicting doom.

The pest control pros that I've interacted with in the past (I currently work with these guys: http://www.fischerspestcontrol.com) have all been extremely careful in their use of chemicals. No one sprays pesticides around willy-nilly, for a few reasons:1: We're afraid of the chemicals ourselves2: Customers are afraid of the chemicals3: We do more business by being as green as possible4: Our industry is very competitive, and customers need to stay happy all the time.

All chemicals are not evil, and all chemical users are not destroyers of the environment.

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About Me

I have served as entomology specialist for Texas AgriLife Extension since 1989. I get to work with, and for, a bunch of great people including pest management professionals, school facilities managers, extension volunteers, researchers and other extension professionals. My areas of specialty center on research on insects affecting man including spiders, scorpions, fire ants, termites and others. My program also focuses on training school maintenance professionals in principles of integrated pest management (IPM). Our goal is to make schools healthier, cleaner places to study and live.